Internal anchor device for wells



Nov. 19, 1940. J. cox Em.

v INTERNAL ANCHOR DEVICE FOR WELLS I Filed Aug. 10, 1939 L4 Tron/vs 35 stru'ction'of an anchor mechanism which is not pull on the head A when the bridge is in upright 85 5 ahead or hub having a groove or pockets'G cir- D will force the arms D into extended position, to

Patented N .1-9,:194o. I 2,222,405

UNITED STATES PATENT. ol-Fries INTERNALANCHOR DEVICE FOR watts Irving J. Cox, Wilmington, DeL, and Charles B Johnson, Glen Mills, Pa. assignors to E; l du Pont de Nemours'& Company, W v gton, Del., a. corporation of Delaware 7 Application August 10, 1939, Serial No. 289,378

6 Claims. (01.166-13) This invention relates to improvements in incomes to rest upon anobstruction such as charges ternal anchor devices. for oil, gas, water, and of explosives previously seated in the well. The other wells, such as .are used to support torarms D are provided with lugs D to engage in pedoes or other explosive devices or charges in the pockets or groove G of the hub A soas to be operative position within the wells. The anchor actuated by the'weight of the hub to bring the device of the present invention is adapted pararms into operative position to engage thev walls ticularly' for selectively arresting the movement of the well or of the well casing when an obstrucof torpedoes or other explosive devices upward or tion is encountered, such as would indicate that downward within the well, for temporarily the desired point for placing the anchor in the plugging the well, or for sustaining the weight well'has been reached. 10

of one or more torpedoes secured to it. As illustrated in Figure -1, the device is shown Devices heretofore used for the purpose" of with the arms D in extended position to engage plugging oil wells, or for supporting'stemming the side wall of the well to support the weight material to close the-bore of wells at predeof a load above, or -achar of explosives $115- termined points have comprised such means as pended from it.. In the event it is de d to use 15 are shown, for example, in the patents to Robin the bridge to prevent upward movement of the son 1,092,508, Fox 1,875,583, and Kingsley 1,979,- char e Series Of c arges in a well, 0 -P 802. The 'patent to McFadden 1,419,068 also vent upward movement of sand or other material shows an anchor means for supp rting a load in y Pr from low, the bridge ne 31 be a well'while drilling. inverted when lowered in the well. In the in- 20 An object of the present invention is the'prov 'p l l he weight ofthe sp r B W vision ofan'inter'nal anchor device of the charcause the arms D to become extended, t us to acter specified which, when used for maintaining engage h W ll Of the well or of the W ll e i torpedoes or other'explosive'charges in position to pr ve p r movement'- Inthis p i 26 in the well, will, upon explosion-of the shot, be When pressure is. app from below a ainst t e broken topieces and fall to the bottom of the h h ad A, such p su e -t force the well soas not to form obstructions therein. arms D into ev n o e p s ve engagement t A further object-.ofthis invention-is'a, devic of the walls of the well or ofthe well casing. the character described which will b fiight While the necessity. for'removal from awell of.

80 weight but at the same time capable of supportan explosive h r e, and eoineident-therewith 30 mg the weight of 1 or more torpedo charges, or. he bridge or Se ies of bridges for Secu i e in case of use for temporarily plugging a well, char e in Pl e-' e t, Su removal 0- will support a substantial load of material. eesienelly becomes a ve. a can i y Another object of the. invention "is the con; be accomplished, by h Present v n n y only economicalbut simple tomanufacture and Position, y a P n the Spider when the which will be not only-reliable, but'prompt and bridge is in inverted position in the well. positive in its action'in'assumin'g an operative O e a ive-The Operation oi the device will position in 'a well. become apparent from the foregoing. The 40 The foregoing objects are attained by a device bridge isse for x mpl t a charge of ex- '40 of the character illustrated in the accomp'anyplosives y m a s h ears F. F; n i thu mg drawing showing a specific bodim t lowered into a well by means of a cable secured thereof, in which Figure 1 is a vertical elevation to h ars E- The Weight of the load holds- '.0f th device presenting a portion in sectional the elements A, B, in extended position, with the a view, and'Figurez i plan view showing the arms D closed, as shown in dotted position in-'45 arms extended and in-operative position to en- Figured. When the charge reaches the bottom gage the walls of a well; Figure 3 illustrate of the well, the pull on the cable connected to the modified form-of arm member or'fluke. head or hub A is thus-released and the weight Referring more particularly to'Flgure 1, A is oi the headbean'ng on the'lugs D of the arm -"cumi'erentially arranged intermediate its ends. as shown in Figure 2. Wi the rid e in'this B is a spider comprisinga base member having a position the arms engage the walls or casing of series of vertical posts or clevises'C. towhich are the well sufliciently to support further charges pivoted arms D adapted to extend substantially of explosives or other load lowered from above radially when the lower memberor spider B to rest on the head or hub A.-

Modification.1n some cases it may be desiri able to provide a knuckle-joint in the arms D to permit free movement in one direction in the vided to bear against the pivoted portion to force L released to support the load carried below or I it in to normal position.

' Not infrequently shale, silt, or like material within the well, particularly below the casing, prevents the proper functioning of the. elements of a mechanical device of the nature of the present invention. When it isessential to avoid the undesirable efiects of such material on the proper operation of the anchor, particularly in raising the anchor and charge in the well, the modified form of arm shown in Figure 3 may be used. It will thus be seen that in any reverse movement of the anchor means by a pull on the head A, or otherwise, should the arms not fold in the normal position as indicated in the dotted position shown in Figure 1, the pointed ends ofthe arms DD will'move downward against the springs, H and thus offer no resistance. When the obstruction is passed, or in the event the anchor is again above, the spring H will force the pointed end of the arms DD back to normal position as shown in the drawing to engage the wall or casing of the well.

From the foregoing the advantages of this invention for the purpose described are at once apparent. The device constructed in accordance with the embodiment illustrated in the accompanying drawing is simple but,positive in its action and is constructed of a minimum of moving parts as contrasted with prior art bridges intended for similar. purposes but involving complicated and costly mechanism which increase.

the opportunity for failures in operation. Since the function of such bridges is performed at great depth in wells and independent of outside aid or control, thus depending on automatic operation,

the positive action of the elements and simplicity of the parts of such a device is of paramount importance. The device is also suitable for use generally as a blasting plug in mining and blasting operations.

While we have described and illustrated herein a preferred embodiment of our invention, it will be apparent therefrom that various modifications thereof may be made without departing from 2. An anchor device for wells comprising a2 hub, a spider slidably mounted on the hub and in collapsible relation therewith, movable arms secured to the .spider and actuated to expansible position by the hub when the hub is being seated in the spider.

3. An anchor device for wells comprising a hub,

' a spider slidably mounted upon the hub, a series of arms pivotally secured to the spider and actuated by the hub upon sliding movement of the hub relative to the spider to open or close the arms.

4. An anchor device for wells comprising a hub, a spider slidably mounted upon the hub, a series of clevises secured to the spider, arms pivotally mounted on the clevises for engaging the walls of the well, and means on the hub for actuating the arms.

5. The anchor device of claim 1 in which the arms are knuckle-jointed intermediate their ends.

6. The anchor device of claim 2 inwhich the 40 arms are knuckle-jointed intermediate their ends.

IRVING J. COX. CHARLES R. JOHNSON. 

